1. Field of the Invention
The present invention relates to an image forming apparatus that manages the life of its component.
2. Description of the Related Art
Conventionally, an image forming apparatus such as a copier disclosed in Japanese Patent Publication No. 2004-226921 (Patent Document 1) below includes a replaceable expendable image forming unit and gives notice of replacement of the image forming unit performing life management.
The conventional image forming apparatus sometimes becomes impossible to detect automatically a lowered quality of printing caused by the expendable image forming unit. In other words, some faults are found by user's decision. If that type of fault occurs, the maintenance agency replaces the expendable item with a new one. If an expendable item having a given length of lifespan is provided, accurate life management becomes impossible after the expendable item is replaced.